<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .box {
        /* 容器 */
        display: flex;
        flex-direction: row-reverse;
        justify-content: space-between;
        width: 500px;
        height: 500px;
        border: 2px solid red;
        margin: 50px auto;
      }

      .child {
        width: 80px;
        height: 80px;
      }

      .child1 {
        background-color: pink;
      }

      .child2 {
        /* 子项目 */
        background-color: skyblue;
        align-self: flex-end;
      }
    </style>
  </head>
  <body>
    <div class="box">
      <div class="child child1"></div>
      <div class="child child2"></div>
    </div>
  </body>
</html>
